anyone know how much hp is lost per 1000 ft or so eleation?

and a reasonably accurate idea of hp vs air temp. i've been told it's roughly 1% for every 10 degrees, but does anyone have a better idea?

thanks

 

SAE J1349

 

gracias...now i gotta find my damn calculator

 

This online calculator is probably somewhat accurate for most calculations:
http://www.wahiduddin.net/calc/calc_hp_dp.htm

There is also this one for force-inducted engines. I have only briefly looked at the calculations, but it seems like the guy has a good point.
http://home.austin.rr.com/turbolexus..._Dyno_Calc.htm

 

those are both great, but i don't have all the necessary info to plug in.
thanks for the help though, i'll make sure to pay attention to all those parameters next time.

 

Sea level is 29.92 inches of mercury. Divide outside air pressure in inches of mercy by 29.92 and that should be about your hp loss.

this chart was meant for airplanes. But pressure loss is linear up to 35,000 feet or so.